I just returned from vacation 10 minutes ago, so I am coming late to
this discussion, but, for what it's worth, Mel Thurman has apparently
been collecting info on French earthfast buildings for a few years.
He discussed with me at various times in 1992 and 93 the possibility
of putting together a large book in which we reviewed the English and
French earthfast traditions in eastern and central US. I never
followed that suggestion up, but Mel may be sitting on a compilation
of the French site evidence.
 
For those relatively new to post-in-ground buildings (not YOU, Ann),
one thing that keeps any such magnum opus compiliation nigh well
impossible is that we dig up several dozens more each year, from all
centuries, I should add, at least in the Cheapeake.
 
Dan Mouer